Project Summary The objective of this application is to request funds for continued support and maintenance of the U42 supported SPF Indian-origin rhesus monkey breeding colony at the TNPRC. During the current funding period the colony has been maintained at a level of approximately 800 animals. This was a management decision based on the demand from NIH funded AIDS researchers and available funds to support the colony. Going forward we expect to expand production in the next few years based on recent developments in funding and animal demand. The specific aims address the components specified in the funding opportunity announcement (FOA) and are divided into the overall program description, husbandry core, viral testing core and genetics/MHC core. Program income (and Center funds) will be used to fund components of the program not covered by grant funds including: per diem for any colony animals in excess of the 800 supported by this application, testing for those animals, infrastructure repairs and improvements, veterinary support for all of the U42 colony animals, behavioral management support, and portions of the genetic testing for the entire U42 colony. Specific Aims: Overall. To maintain the existing SPF colony and distribute available animals to the NIH funded AIDS research community. Husbandry and Management. To provide husbandry and veterinary care for the SPF breeding colony established in the existing U42 grant. This includes a robust program for clinical veterinary medical care and behavioral management. The colony has reached a mature self sustaining status with ideal demographics to produce up to 150 animals available for assignment each year. Program Income generated by the sale of animals will be returned to an account for use in supporting the aims of the grant. Viral Testing. To assure the SPF status of the colony through continued viral testing of existing breeding colony animals and all offspring. Expand characterization of the colony beyond the required 4 viruses to include agents such as measles virus and Trypanosoma cruzi. Genetic/MHC typing . To continue genetic analysis and MHC typing of the colony and provide expanded genetic characterization through enhanced techniques.